If a server instance that you select to host an availability replica is running under a domain user account and does not yet have a database mirroring endpoint, the wizard can create the endpoint and grant CONNECT permission to the server instance service account. However, if the SQL Server service is running as a built-in account, such as Local System, Local Service, or Network Service, or a nondomain account, you must use certificates for endpoint authentication, and the wizard will be unable to create a database mirroring endpoint on the server instance. In this case, we recommend that you create the database mirroring endpoints manually before you launch the Add Replica to Availability Group Wizard.

All the database-file paths must be identical on every server instance that hosts a replica for the availability group.

No primary database name can exist on any server instance that hosts a secondary replica. This means that none of the new secondary databases can exist yet.

You will need to specify a network share in order for the wizard to create and access backups. For the primary replica, the account used to start the Database Engine must have read and write file-system permissions on a network share. For secondary replicas, the account must have read permission on the network share.

Use this tab to specify each instance of SQL Server that will host a new secondary replica.

Endpoints

Use this tab to verify the existing database mirroring endpoint, if any, for each new secondary replica. If this endpoint is lacking on a server instance whose service accounts use Windows Authentication, the wizard will attempt to create the endpoint automatically.

Note

If any server instance is running under a non-domain user account, you need to do make a manual change to your server instance before you can proceed in the wizard. For more information, see Prerequisites, earlier in this topic.

Backup Preferences

Use this tab to specify your backup preference for the availability group as a whole, if you wish to modify the current setting, and to specify your backup priorities for the individual availability replicas.

On the Select Initial Data Synchronization page, choose how you want your new secondary databases to be created and joined to the availability group. Choose one of the following options:

Full

Select this option if your environment meets the requirements for automatically starting initial data synchronization (for more information, see Prerequisites, Restrictions, and Recommendations , earlier in this topic).

If you select Full, after creating the availability group, the wizard will back up every primary database and its transaction log to a network share and restore the backups on every server instance that hosts a new secondary replica. The wizard will then join every new secondary database to the availability group.

In the Specify a shared network location accessible by all replicas: field, specify a backup share to which all of the server instance that host replicas have read-write access. The log backups will be part of your log backup chain. Store the log backup files appropriately.

Security Note

For information about the required file-system permissions, see Prerequisites, earlier in this topic.

Join only

If you have manually prepared secondary databases on the server instances that will host the new secondary replicas, you can select this option. The wizard will join these new secondary databases to the availability group.

The Validation page verifies whether the values you specified in this Wizard meet the requirements of the Add Replica to Availability Group Wizard. To make a change, click Previous to return to an earlier wizard page to change one or more values. The click Next to return to the Validation page, and click Re-run Validation.

On the Summary page, review your choices for the new availability group. To make a change, click Previous to return to the relevant page. After making the change, click Next to return to the Summary page.

If you are satisfied with your selections, optionally click Script to create a script of the steps the wizard will execute. Then, to create and configure the new availability group, click Finish.

The Progress page displays the progress of the steps for creating the availability group (configuring endpoints, creating the availability group, and joining the secondary replica to the group).

When these steps complete, the Results page displays the result of each step. If all these steps succeed, the new availability group is completely configured. If any of the steps result in an error, you might need to manually complete the configuration. For information about the cause of a given error, click the associated "Error" link in the Result column.